System and method for aligning passenger boarding bridges

ABSTRACT

A sensor is disposed aboard an aircraft for sensing movement of a passenger boarding bridge during an automated alignment operation. Determinations are made whether the actual sensed movements of the passenger boarding bridge correspond to expected movements of the passenger boarding bridge for a current alignment operation. If the sensed movements do not correspond to the expected movements, then a transmitter aboard the aircraft is used to transmit an anti-collision signal to an automated controller of the passenger boarding bridge.

FIELD OF THE INVENTION

The instant invention relates generally to passenger boarding bridges,and more particularly to a system and method for aligning a passengerboarding bridge with a craft in a fully automated manner.

BACKGROUND

In order to make aircraft passengers comfortable, and in order totransport them between an airport terminal building and an aircraft insuch a way that they are protected from the weather and from otherenvironmental influences, passenger boarding bridges are used which aretelescopically extensible and the height of which is adjustable. Forinstance, an apron drive bridge in present day use includes a pluralityof adjustable modules, including: a rotunda, a telescopic tunnel, abubble section, a cab, and elevating columns with wheel carriage. Othercommon types of passenger boarding bridges include radial drive bridgesand over-the-wing (OTW) bridges. Manual, semi-automated andfully-automated bridge alignment systems are known for adjusting theposition of the passenger boarding bridge relative to an aircraft, tocompensate for different sized aircraft and to compensate for impreciseparking of aircraft.

A manual bridge alignment system requires that a human operator ispresent to perform the alignment operation each time an aircraftarrives. Delays occur when the human operator is not standing-by toperform the alignment operation as soon as the aircraft comes to a stop.In addition, human operators are prone to errors that result in thepassenger boarding bridge being driven into the aircraft or into a pieceof ground service equipment. Such collisions involving the passengerboarding bridge are costly and also result in delays. In order to avoidcausing a collision, human operators tend to err on the side of cautionand drive the bridge slowly and cautiously.

Semi-automated bridge alignment systems also require a human operator,but the human operator may be present at a remote location and interactwith the bridge control system in a tele-robotic manner. One humanoperator may interact with a plurality of different passenger boardingbridges, thereby reducing the costs associated with training and payingthe salaries of human operators. Alternatively, certain movements of thebridge are automated, whilst other movements are performed under thecontrol of the human operator.

Automated bridge alignment systems provide a number of advantagescompared to manual and semi-automated systems. For instance, automatedbridge alignment systems do not require a human operator, and thereforethe costs that are associated with training and paying the salaries ofhuman operators are reduced or eliminated. Furthermore, an automatedbridge alignment system is always standing by to control the passengerboarding bridge as soon as an aircraft comes to a stop. Accordingly,delays associated with dispatching a human operator to perform a bridgealignment operation are eliminated, particularly during periods of heavyaircraft travel.

Early attempts at automated bridge alignment systems employed imagersand sensors disposed on or about the bridge, for sensing locations ofaircraft doorways and for sensing close approach of the bridge to theaircraft. More recently, automated bridge alignment systems have beendeveloped in which beacon docking signals and/or control signals aretransmitted wirelessly between an aircraft and a passenger boardingbridge, as described for example in U.S. Pat. Nos. 6,637,063, 6,742,210,6,757,927 and 6,907,635, the entire contents of all of which areincorporated by reference herein. In such systems, the aircraft plays anactive role in the bridge alignment operation, rather than a purelypassive one. Other systems relying upon wireless transmission of signalsbetween an aircraft and a passenger boarding bridge during alignment aredisclosed in co-pending U.S. applications Ser. Nos. 11/149,401,11/155,502, 11/157,934 and 11/157,938, the entire contents of all ofwhich are also incorporated by reference herein. Unfortunately,automated bridge alignment systems also are prone to errors that resultin the passenger boarding bridge being driven into the aircraft. Forinstance, in a system in which an aircraft wirelessly transmits a callsignal for initiating an automated alignment operation of a passengerboarding bridge, it is possible that a neighboring bridge may interceptthe signal and begin to move under the control of the aircraft. As aresult, the neighboring bridge may collide with a different aircraft orwith ground service equipment located adjacent thereto. With the growingnumber of automated bridge alignment systems that are in use atairports, the problem of ensuring proper communication between anaircraft and a passenger boarding bridge is becoming more of a concern.

It would be advantageous to provide a system and method that overcomesat least some of the above-mentioned limitations.

SUMMARY OF EMBODIMENTS OF THE INVENTION

In accordance with an aspect of the instant invention there is provideda system for aligning in an automated fashion an aircraft-engaging endof a passenger boarding bridge to a doorway of an aircraft, thepassenger boarding bridge equipped with a controller and a drive system,the controller for providing first control signals to the drive systemfor effecting a movement of the aircraft-engaging end along a directiontoward the doorway of the aircraft, the system comprising: a transmitterdisposed aboard the aircraft for wirelessly transmitting second controlsignals to the controller, the second control signals for use by thecontroller in determining the first control signals; a sensor disposedaboard the aircraft for sensing movement of the passenger boardingbridge during a current alignment operation; and, a processor incommunication with the sensor for receiving therefrom data relating tothe sensed movement of the passenger boarding bridge, and for comparingthe data to other data relating to an expected movement of the passengerboarding bridge based upon the transmitted second control signals.

In accordance with another aspect of the instant invention there isprovided a method for aligning in an automated fashion anaircraft-engaging end of a passenger boarding bridge to a doorway of anaircraft, the method comprising: transmitting a signal from the aircraftto an automated controller of the passenger boarding bridge, the signalfor initiating a desired movement of the passenger boarding bridgeduring a current bridge alignment operation; during the current bridgealignment operation, using a sensor disposed aboard the aircraft tosense an actual movement of the passenger boarding bridge; comparing theactual movement to the desired movement; and, if the actual movementdiffers from the desired movement by more than a predetermined thresholdvalue, using the transmitter to transmit an anti-collision signal.

In accordance with another aspect of the instant invention there isprovided a method for aligning in an automated fashion anaircraft-engaging end of a passenger boarding bridge to a doorway of anaircraft, the method comprising: parking the aircraft within a parkingspace that is adjacent to the passenger boarding bridge; using a sensordisposed aboard the aircraft, sensing an initial position of thepassenger boarding bridge relative to the aircraft for a currentalignment operation; during the current alignment operation, using thesensor to sense movements of the passenger boarding bridge from theinitial position along a direction toward the doorway of the aircraft;comparing the sensed movements of the passenger boarding bridge withexpected movements of the passenger boarding bridge for the giveninitial position of the passenger boarding bridge; and, if the sensedmovements differ from the expected movements by more than apredetermined threshold value, using a transmitter disposed aboard theaircraft to transmit an anti-collision signal.

In accordance with another aspect of the instant invention there isprovided a method for establishing communication between a passengerboarding bridge and an aircraft, comprising: parking the aircraft withina parking space that is adjacent to the passenger boarding bridge; usinga sensor disposed aboard the aircraft, sensing movements of thepassenger boarding bridge; comparing the sensed movements of thepassenger boarding bridge with expected movements of the passengerboarding bridge, the expected movements comprising a predeterminedsequence of movements; and, when the sensed movements and the expectedmovements are the same to within predetermined threshold values,aligning the passenger boarding bridge with a doorway of the aircraft inan automated fashion.

In accordance with another aspect of the instant invention there isprovided a method for establishing communication between a passengerboarding bridge and an aircraft, comprising: waiting for an aircraft toapproach a parking space that is adjacent to the passenger boardingbridge; performing a predetermined sequence of movements of thepassenger boarding bridge for providing a visually distinguishableindication that the passenger boarding bridge is in a condition forbeing aligned with a doorway of the aircraft; receiving a signaltransmitted from the aircraft for initiating an automated bridgealignment operation, the signal for indicating that the predeterminedsequence of movements conformed with expected movements to within apredetermined threshold value; in dependence upon receiving the signalfrom the aircraft, initiating an automated alignment operation of thepassenger boarding bridge to the doorway of the aircraft.

In accordance with another aspect of the instant invention there isprovided a method for establishing communication between a passengerboarding bridge and an aircraft, comprising: waiting for an aircraft toapproach a parking space that is adjacent to the passenger boardingbridge; performing a predetermined sequence of movements of thepassenger boarding bridge for providing a visually distinguishableindication that the passenger boarding bridge is in a condition forbeing aligned with a doorway of the aircraft; receiving a signaltransmitted from the aircraft for initiating an automated bridgealignment operation, the signal for indicating that the predeterminedsequence of movements conformed with expected movements to within apredetermined threshold value; in dependence upon receiving the signalfrom the aircraft, initiating an automated alignment operation of thepassenger boarding bridge to the doorway of the aircraft.

BRIEF DESCRIPTION OF THE DRAWINGS

Exemplary embodiments of the invention will now be described inconjunction with the following drawings, in which similar referencenumerals designate similar items:

FIG. 1 a is a simplified top view of a passenger boarding bridge in astowed position relative to a nose-in parked aircraft;

FIG. 1 b is a simplified top view of the passenger boarding bridge ofFIG. 1 a in an intermediate position relative to the nose-in parkedaircraft;

FIG. 1 c is a simplified top view of the passenger boarding bridge ofFIG. 1 a in an aircraft engaging condition relative to the nose-inparked aircraft;

FIG. 2 is a partial side view of an aircraft equipped with a sensoraccording to an embodiment of the instant invention;

FIG. 3 is a simplified flow diagram of a method according to anembodiment of the instant invention;

FIG. 4 is a simplified flow diagram of another method according to anembodiment of the instant invention;

FIG. 5 is a simplified flow diagram of a method for establishingcommunication between a passenger boarding bridge and an aircraftaccording to an embodiment of the instant invention;

FIG. 6 is a simplified flow diagram of another method for establishingcommunication between a passenger boarding bridge and an aircraftaccording to an embodiment of the instant invention; and,

FIG. 7 is a simplified flow diagram of a method for aligning in anautomated fashion an aircraft-engaging end of a passenger boardingbridge to a doorway of an aircraft, according to an embodiment of theinstant invention.

DESCRIPTION OF EMBODIMENTS OF THE INVENTION

The following description is presented to enable a person skilled in theart to make and use the invention, and is provided in the context of aparticular application and its requirements. Various modifications tothe disclosed embodiments will be readily apparent to those skilled inthe art, and the general principles defined herein may be applied toother embodiments and applications without departing from the spirit andthe scope of the invention. Thus, the present invention is not intendedto be limited to the embodiments disclosed, but is to be accorded thewidest scope consistent with the principles and features disclosedherein.

Referring to FIG. 1 a, shown is a simplified top view of a passengerboarding bridge in a stowed position relative to a nose-in parkedaircraft. The passenger boarding bridge 2 comprises a rotunda 4, whichis connected to a terminal building 6 and from which extends apassageway 8. The passageway 8 ends with a pivotable cabin 10 andincludes inner 12 and outer 14 passageway elements, wherein the innerelement 12 is telescopically received within the outer element 14 suchthat the length of the passageway 8 is variable. Of course, eachpassageway element includes a left sidewall, a right sidewall, a floormember and a ceiling member. Optionally, a number of passageway elementsother than two are provided. An automated controller 16 is provided incommunication with a not illustrated drive system of the passengerboarding bridge. The automated controller provides first control signalsto the drive system for extending the length of the passageway 8, foradjusting the height of the passageway 8, for angularly adjusting thepassageway 8 and for pivoting the pivotable cabin 10. Also shown in FIG.1 is an aircraft 18 with a door 20, for instance a front left door ofthe aircraft, to which the passenger boarding bridge 2 is to beconnected. The aircraft 18 is equipped with a sensor 22, a processor 24,and a transmitter 26.

According to the instant embodiment, the sensor 22 is an imager,optionally one of a digital still camera and a digital video camera.Optionally, a different type of sensor, such as for instance a laserrange finder, is provided in place of the imager or in addition to theimager. The transmitter 26 is a wireless transmitter, such as forinstance one of a radio-frequency (RF) transmitter and an opticaltransmitter. The transmitter 26 is for transmitting signals from theaircraft 18 to a not illustrated receiver that is in communication withthe automated controller 16 of the passenger boarding bridge 2. Thesensor 22 is in communication with the processor 24 for providing datathereto, the data relating to sensed positional information of thepassenger boarding bridge 2 for a current alignment operation. Forinstance, the sensor 22 in the form of a digital video camera captures avideo segment of passenger boarding bridge 2 movements, and video datais provided to the processor 24. The processor 24 processes the videodata to extract information relating to the bridge movement, using imageprocessing techniques that are known to one of skill in the art.Alternatively, the processing is performed for a series of at least twostill images, which are obtained at a known interval of time.

Alternatively, the sensor 22 is an individual aboard the aircraft. Theindividual is prompted to watch the bridge and determine whether thebridge moves in an expected manner. Optionally, the individual providesbridge control commands via a user interface, and then watches thebridge to confirm that the bridge moves as commanded. Optionally, theindividual simply watches for the a predetermined series of movements ofthe passenger boarding bridge, which are performed in response tosensing the aircraft within the parking space adjacent to the passengerboarding bridge.

Two types of automated boarding bridge alignment systems are nowconsidered. In a first system, the processor 24 determines instructionsfor use by the automated controller 16 during a current alignmentoperation. In particular, the instructions are for moving the pivotablecabin 10 located at the aircraft-engaging end of the passenger boardingbridge 2 toward doorway 20 of aircraft 18. To this end, the sensor 22senses an initial position of the passenger boarding bridge relative tothe aircraft 18 for the current alignment operation. The processor 24determines instructions for initiating movements of the passengerboarding bridge 2 toward the doorway 20, and provides data relating tothe determined instructions to transmitter 26. Transmitter 26 transmitsthe determined instructions, in the form of second control signals, tothe not illustrated receiver in communication with the automatedcontroller 16. The automated controller 16 receives the second controlsignals, and determines or otherwise provides first control signals tothe not illustrated drive system of passenger boarding bridge 2.Referring now to FIG. 1 b, the sensor 22 continues to sense positionalinformation as the passenger boarding bridge 2 moves along “path A”, andprovides data relating to sensed bridge movement to the processor 24.The processor compares the data relating to sensed bridge movement withdata relating to an expected movement of the passenger boarding bridgefor the given initial position of the passenger boarding bridge. If thesensed bridged movement differs from the expected movement by more thana predetermined threshold value, then processor 24 provides ananti-collision signal for transmission via transmitter 26 to thenot-illustrated receiver in communication with the automated controller16. By way of non-limiting example, the anti-collision signal isoptionally one of an emergency stop signal and a retract bridge signalfor being executed by the automated controller. Optionally, theanti-collision signal bypasses the automated controller 16 and powersdown the passenger boarding bridge 2 directly. In the latter case, acollision is avoided even if there is a problem with the automatedcontroller's 16 ability to correctly implement the instructions that areprovided from processor 24.

Of course, if the sensed bridge movement approximates the expectedmovement, then the alignment operation continues with the passengerboarding bridge 2 moving along “path B” as shown in FIG. 1 c. The sensor22 continues to sense positional information as the passenger boardingbridge 2 moves along “path B”, and the processor 24 continues to comparethe sensed bridge movement with expected movement, until the pivotablecabin 8 engages the aircraft 18 and the bridge drive system is partiallypowered down or placed in a standby state.

In a second system, the transmitter 26 transmits a beacon signal to thenot illustrated receiver in communication with the automated controller16. The automated controller 16 provides first control signals to thenot illustrated drive system for “homing-in” on the beacon signal.During use, the aircraft 18 is parked adjacent to the passenger boardingbridge 2, and the sensor 22 senses an initial position of the passengerboarding bridge 2 relative to the aircraft 18. The transmitter 26 beginstransmitting a beacon signal, which initiates automated alignment of thepassenger boarding bridge 2 with doorway 20 of aircraft 18. Based uponthe initial position of the passenger boarding bridge 2 relative to theaircraft 18, the processor 24 determines expected movement of thepassenger boarding bridge 2 for the current alignment operation.Referring now to FIG. 1 b, the sensor 22 continues to sense positionalinformation as the passenger boarding bridge 2 moves along “path A”, andprovides data relating to sensed bridge movement to the processor 24.The processor compares the data relating to sensed bridge movement withdata relating to expected movement of the passenger boarding bridge forthe given initial position of the passenger boarding bridge. If thesensed bridged movement differs from the expected movement by more thana predetermined threshold value, then processor 24 provides ananti-collision signal for transmission via transmitter 26 to thenot-illustrated receiver in communication with the automated controller16. By way of non-limiting example, the anti-collision signal isoptionally one of an emergency stop signal and a retract bridge signalfor being executed by the automated controller. Optionally, theanti-collision signal bypasses the automated controller 16 and powersdown the passenger boarding bridge 2 directly. In the latter case, acollision is avoided even if there is a problem with the automatedcontroller's 16 ability to correctly implement the instructions that areprovided from processor 24.

Of course, if the sensed bridge movement approximates the expectedmovement, then the alignment operation continues with the passengerboarding bridge 2 moving along “path B” as shown in FIG. 1 c. The sensor22 continues to sense positional information as the passenger boardingbridge 2 moves along “path B”, and the processor 24 continues to comparethe sensed bridge movement with expected movement, until the pivotablecabin 8 engages the aircraft 18 and the bridge drive system is partiallypowered down or placed in a standby state.

Referring now to FIG. 2, shown is partial side view of an aircraftequipped with a sensor according to an embodiment of the instantinvention. As shown in FIG. 2, the sensor 22 is optionally disposedproximate the doorway 20. By way of non-limiting example, the sensor 22is mounted within the space normally occupied by a lamp for illuminatingthe area around the doorway 20. Optionally, the sensor 22 is mountedinside the aircraft cabin adjacent to a window surface. Preferably, thesensor is mounted as close to doorway 22 as possible, such that thesensor may follow the movement of the pivotable cabin 8 all the way upuntil the point the aircraft is engaged.

Referring now to FIG. 3, shown is a simplified flow diagram of a methodaccording to an embodiment of the instant invention. At step 300 asignal is transmitted from the aircraft to an automated controller ofthe passenger boarding bridge, the signal for initiating a desiredmovement of the passenger boarding bridge during a current bridgealignment operation. At step 302, during the current bridge alignmentoperation, a sensor disposed aboard the aircraft is used to sense anactual movement of the passenger boarding bridge. At step 304 aprocessor disposed aboard the aircraft compares the actual movement tothe desired movement. At step 306 a determination is made whether theactual movement differs from the desired movement by more than apredetermined threshold value. If it is determined that the actualmovement differs from the desired movement by more than a predeterminedthreshold value, then a transmitter aboard the aircraft is used totransmit an anti-collision signal to an automated controller of thepassenger boarding bridge. By way of non-limiting example, theanti-collision signal is optionally one of an emergency stop signal anda retract bridge signal for being executed by the automated controller.Optionally, the anti-collision signal bypasses the automated controllerand powers down the passenger boarding bridge directly.

Referring now to FIG. 4, shown is a simplified flow diagram of anothermethod according to an embodiment of the instant invention. At step 400the aircraft is parked within a parking space that is adjacent to thepassenger boarding bridge. At step 402 a sensor disposed aboard theaircraft is used to sense an initial position of the passenger boardingbridge, relative to the aircraft, for a current alignment operation. Atstep 404 the sensor is used during the current alignment operation tosense movements of the passenger boarding bridge from the initialposition, along a direction toward the doorway of the aircraft. At step406 the sensed movements of the passenger boarding bridge are comparedwith expected movements of the passenger boarding bridge, the expectedmovements based upon the sensed initial position of the passengerboarding bridge and the known position of the doorway of the aircraftrelative to the sensor. At step 408 a determination is made whether thesensed movements differs from the desired movement by more than apredetermined threshold value. If it is determined that the sensedmovements differ from the desired movement by more than thepredetermined threshold value, then a transmitter aboard the aircraft isused to transmit an anti-collision signal to an automated controller ofthe passenger boarding bridge. By way of non-limiting example, theanti-collision signal is optionally one of an emergency stop signal anda retract bridge signal for being executed by the automated controller.Optionally, the anti-collision signal bypasses the automated controllerand powers down the passenger boarding bridge directly.

Referring now to FIG. 5, shown is a simplified flow diagram of a methodfor establishing communication between a passenger boarding bridge andan aircraft according to an embodiment of the instant invention. At step500 the aircraft is parked within a parking space that is adjacent tothe passenger boarding bridge. At step 502, a sensor that is disposedaboard the aircraft is used to sense movements of the passenger boardingbridge. At step 504 the sensed movements of the passenger boardingbridge are compared with expected movements of the passenger boardingbridge, the expected movements comprising a predetermined sequence ofmovements. At step 506, when the sensed movements and the expectedmovements are the same to within predetermined threshold values, thepassenger boarding bridge is aligned with a doorway of the aircraft inan automated fashion. Optionally, a signal is transmitted from theaircraft to an automated bridge controller for initiating an automatedbridge alignment process, in dependence upon the sensed movements andthe expected movements being the same to within predetermined thresholdvalues. Alternatively, the automated bridge controller initiates theautomated alignment process unless the aircraft transmits a signal foraborting the automated alignment process.

The predetermined sequence of movements is for providing a visuallydistinguishable indication that the passenger boarding bridge is in acondition for being aligned with the doorway of the aircraft. In otherwords, the predetermined sequence of movements is a “visual handshake”between an automated bridge controller of the passenger boarding bridgeand the aircraft. Optionally, a person disposed aboard the aircraft isobserves the predetermined sequence of movements and determines whetheror not to allow the automated alignment process to proceed.

Referring now to FIG. 6, shown is a simplified flow diagram of a methodfor establishing communication between a passenger boarding bridge andan aircraft according to an embodiment of the instant invention. Step600 is a step of waiting for an aircraft to approach a parking spacethat is adjacent to the passenger boarding bridge. At step 602, apredetermined sequence of movements of the passenger boarding bridge isperformed. The predetermined sequence of movements is for providing avisually distinguishable indication that the passenger boarding bridgeis in a condition for being aligned with a doorway of the aircraft. Inother words, the predetermined sequence of movements is a “visualhandshake” between an automated bridge controller of the passengerboarding bridge and the aircraft. At step 604 a signal transmitted fromthe aircraft is received using a receiver disposed aboard the passengerboarding bridge. The signal transmitted from the aircraft is forinitiating an automated bridge alignment operation. The signal istransmitted in dependence upon the predetermined sequence of movementsconforming with expected movements to within a predetermined thresholdvalue. At step 606, in dependence upon receiving the signal from theaircraft, an automated alignment operation is initiated for aligning thepassenger boarding bridge to the doorway of the aircraft.

Referring now to FIG. 7, shown is a simplified flow diagram of a methodfor aligning in an automated fashion an aircraft-engaging end of apassenger boarding bridge to a doorway of an aircraft, the methodcomprising. At step 700 the aircraft is parked within a parking spacethat is adjacent to the passenger boarding bridge. Using a sensordisposed aboard the aircraft, at step 702 an initial position of thepassenger boarding bridge is sensed relative to the aircraft for acurrent alignment operation. At step 704, during the current alignmentoperation, the sensor is used to sense movements of the passengerboarding bridge from the initial position along a direction toward thedoorway of the aircraft. At step 706, based upon the sensed movements ofthe passenger boarding bridge, a value is determined relating to aprobability of a collision involving the passenger boarding bridge andthe aircraft during the current alignment operation. At step 708, if thedetermined value is outside a range of predetermined threshold values, asignal for aborting the current alignment operation is transmitted fromthe aircraft. If the determined value is within the range ofpredetermined threshold values, then the current alignment operationcontinues and the passenger boarding bridge is aligned with the doorwayof the aircraft in an automated manner.

The embodiments of the instant invention have been described using thespecific and non-limiting example of an apron drive bridge being alignedwith a doorway forward of the wing of an aircraft. However, other typesof passenger boarding bridges including radial drive bridges,over-the-wing (OTW) bridges and dual boarding bridges optionally arealigned with one or more doorways either forward of, above, or aft ofthe wing of the aircraft according to the instant invention.Furthermore, a sensor in the form of an imager has been described, butoptionally other types or additional types of sensors are included. Forinstance, according to an optional embodiment of the instant invention adistance-measuring laser range finder is provided in addition to animaging device.

The embodiments of the instant invention have been described in terms ofusing a sensor disposed aboard the aircraft for sensing movements of thepassenger boarding bridge while the passenger boarding bridge isactually moving toward an aircraft-engaging position. However,optionally the sensed movements are not for moving the passengerboarding bridge along a direction toward the aircraft doorway. Forinstance, optionally the passenger boarding bridge performs apredetermined series of movements prior to beginning the alignmentoperation. Examples of movements include pivoting the cabin fromside-to-side, raising and lowering the passenger boarding bridge, ordriving the passenger boarding bridge angularly across the apron.Optionally, the movements are performed when a parked aircraft is sensedadjacent to the bridge, or in response to a signal being transmittedfrom the aircraft to the passenger boarding bridge. The predeterminedseries of movements is a visual hand-shake between the bridge and theaircraft, to ensure that the correct bridge is attempting to align withthe aircraft. For instance, the aircraft parks within a parking spaceadjacent to the passenger boarding bridge and transmits a call signalfor initiating an automated alignment operation. The passenger boardingbridge performs at least a predetermined movement, while the aircraftuses a sensor to scan the bridge for movement. If the sensor detects thepredetermined movement, then correct communication is confirmed and thealignment operation may proceed. Optionally, the movement is notpredetermined. In this latter case the call signal transmitted from theaircraft includes a command to perform a movement. If the sensor aboardthe aircraft senses the correct movement of the passenger boardingbridge within a predetermined period of time, then correct communicationis confirmed and the alignment operation may proceed.

Numerous other embodiments may be envisaged without departing from thespirit and scope of the invention.

1. A system for aligning in an automated fashion an aircraft-engagingend of a passenger boarding bridge to a doorway of an aircraft, thepassenger boarding bridge equipped with a controller and a drive system,the controller for providing first control signals to the drive systemfor effecting a movement of the aircraft-engaging end along a directiontoward the doorway of the aircraft, the system comprising: a transmitterdisposed aboard the aircraft for wirelessly transmitting second controlsignals to the controller, the second control signals for use by thecontroller in determining the first control signals; a sensor disposedaboard the aircraft for sensing movement of the passenger boardingbridge during a current alignment operation; and, a processor incommunication with the sensor for receiving therefrom data relating tothe sensed movement of the passenger boarding bridge, and for comparingthe data to other data relating to an expected movement of the passengerboarding bridge based upon the transmitted second control signals.
 2. Asystem according to claim 1, wherein the processor is for providing ananti-collision signal for transmission by the transmitter if the sensedmovement differs from the expected movement by more than a predeterminedthreshold value.
 3. A system according to claim 2, wherein theanti-collision signal comprises an emergency-stop command.
 4. A systemaccording to claim 1, wherein the sensor comprises an imager forcapturing an image of the passenger boarding bridge during the currentalignment operation.
 5. A system according to claim 1, wherein thesensor comprises a digital video camera for capturing a video segment ofthe passenger boarding bridge during the current alignment operation. 6.A system according to claim 1, wherein the sensor comprises a digitalstill camera for capturing a series of images of the passenger boardingbridge during the current alignment operation.
 7. A system according toclaim 1, wherein the transmitter is for transmitting the second controlsignals in the form of bridge movement instruction signals for thecurrent alignment operation.
 8. A system according to claim 1, whereinthe transmitter is for transmitting the second control signals in theform of a beacon signal.
 9. A system according to claim 1, comprising auser interface disposed aboard the aircraft for receiving from a user aninput signal relating to a desired bridge movement instruction for thecurrent alignment operation, and for providing an output signal to thetransmitter for transmission thereby, the output signal relating to thedesired bridge movement, the output signal for inclusion in the secondcontrol signals.
 10. A method for aligning in an automated fashion anaircraft-engaging end of a passenger boarding bridge to a doorway of anaircraft, the method comprising: transmitting a signal from the aircraftto an automated controller of the passenger boarding bridge, the signalfor initiating a desired movement of the passenger boarding bridgeduring a current bridge alignment operation; during the current bridgealignment operation, using a sensor disposed aboard the aircraft tosense an actual movement of the passenger boarding bridge; comparing theactual movement to the desired movement; and, if the actual movementdiffers from the desired movement by more than a predetermined thresholdvalue, using the transmitter to transmit an anti-collision signal.
 11. Amethod according to claim 10, wherein the anti-collision signalcomprises an emergency-stop signal.
 12. A method according to claim 10,wherein the anti-collision signal comprises a retract bridge signal. 13.A method according to claim 10, wherein the anti-collision signalcomprises a power-down signal.
 14. A method according to claim 10,wherein sensing the actual movement of the passenger boarding bridgecomprises capturing an image of the passenger boarding bridge.
 15. Amethod according to claim 10, wherein the desired movement is forconfirming a communication link between the aircraft and the automatedcontroller.
 16. A method according to claim 10, wherein the sensor is anindividual aboard the aircraft and wherein transmitting a signal fromthe aircraft comprises the individual providing a command via a userinterface, the command for initiating the desired movement of thepassenger boarding bridge.
 17. A method for aligning in an automatedfashion an aircraft-engaging end of a passenger boarding bridge to adoorway of an aircraft, the method comprising: parking the aircraftwithin a parking space that is adjacent to the passenger boardingbridge; using a sensor disposed aboard the aircraft, sensing an initialposition of the passenger boarding bridge relative to the aircraft for acurrent alignment operation; during the current alignment operation,using the sensor to sense movements of the passenger boarding bridgefrom the initial position along a direction toward the doorway of theaircraft; comparing the sensed movements of the passenger boardingbridge with expected movements of the passenger boarding bridge for thegiven initial position of the passenger boarding bridge; and, if thesensed movements differ from the expected movements by more than apredetermined threshold value, using a transmitter disposed aboard theaircraft to transmit an anti-collision signal.
 18. A method according toclaim 17, wherein the anti-collision signal comprises an emergency-stopsignal.
 19. A method according to claim 17, wherein the anti-collisionsignal comprises a retract bridge signal.
 20. A method according toclaim 17, wherein the anti-collision signal comprises a power-downsignal.
 21. A method according to claim 17, wherein sensing movements ofthe passenger boarding bridge comprises capturing an image of thepassenger boarding bridge.
 22. A method for establishing communicationbetween a passenger boarding bridge and an aircraft, comprising: parkingthe aircraft within a parking space that is adjacent to the passengerboarding bridge; using a sensor disposed aboard the aircraft, sensingmovements of the passenger boarding bridge; comparing the sensedmovements of the passenger boarding bridge with expected movements ofthe passenger boarding bridge, the expected movements comprising apredetermined sequence of movements; and, when the sensed movements andthe expected movements are the same to within predetermined thresholdvalues, aligning the passenger boarding bridge with a doorway of theaircraft in an automated fashion.
 23. A method according to claim 22,wherein the predetermined sequence of movements is for providing avisually distinguishable indication that the passenger boarding bridgeis in a condition for being aligned with the doorway of the aircraft.24. A method according to claim 23, comprising providing a processordisposed aboard the aircraft and in communication with the sensor,wherein the processor is for comparing the sensed movements of thepassenger boarding bridge with expected movements of the passengerboarding bridge.
 25. A method according to claim 22, wherein aligningthe passenger boarding bridge with the doorway of the aircraft comprisestransmitting a command from the aircraft to an automated bridgecontroller, the command for initiating an automated alignment process.26. A method for establishing communication between a passenger boardingbridge and an aircraft, comprising: waiting for an aircraft to approacha parking space that is adjacent to the passenger boarding bridge;performing a predetermined sequence of movements of the passengerboarding bridge for providing a visually distinguishable indication thatthe passenger boarding bridge is in a condition for being aligned with adoorway of the aircraft; receiving a signal transmitted from theaircraft for initiating an automated bridge alignment operation, thesignal for indicating that the predetermined sequence of movementsconformed with expected movements to within a predetermined thresholdvalue; in dependence upon receiving the signal from the aircraft,initiating an automated alignment operation of the passenger boardingbridge to the doorway of the aircraft.
 27. A method according to claim26, wherein the predetermined sequence of movements is performed inresponse to receiving a call signal from the aircraft.
 28. A methodaccording to claim 26, comprising using a sensor disposed aboard thepassenger boarding bridge to sense the approach of the aircraft withinthe parking space that is adjacent to the passenger boarding bridge. 29.A method according to claim 28, wherein the predetermined sequence ofmovements is performed in response to sensing the approach of theaircraft within the parking space that is adjacent to the passengerboarding bridge.
 30. A method according to claim 26, wherein receiving asignal transmitted from the aircraft is performed using a receiverdisposed aboard the passenger boarding bridge and in communication withan automated bridge controller.
 31. A method for aligning in anautomated fashion an aircraft-engaging end of a passenger boardingbridge to a doorway of an aircraft, the method comprising: parking theaircraft within a parking space that is adjacent to the passengerboarding bridge; using a sensor disposed aboard the aircraft, sensing aninitial position of the passenger boarding bridge relative to theaircraft for a current alignment operation; during the current alignmentoperation, using the sensor to sense movements of the passenger boardingbridge from the initial position along a direction toward the doorway ofthe aircraft; based upon the sensed movements of the passenger boardingbridge, determining a value relating to a probability of a collisioninvolving the passenger boarding bridge and the aircraft during thecurrent alignment operation; and, if the determined value is outside arange of predetermined threshold values, transmitting from the aircrafta signal for aborting the current alignment operation.
 32. A methodaccording to claim 31, wherein sensing movements of the passengerboarding bridge comprises capturing images of the passenger boardingbridge during the current alignment operation.
 33. A method according toclaim 31, wherein transmitting a signal for aborting the currentalignment operation comprises transmitting an optical signal.
 34. Amethod according to claim 31, wherein transmitting a signal for abortingthe current alignment operation comprises transmitting a radio frequencysignal.